Question

Statement 1 : $S{O}_2,N{O}_3^{-}$ and $C{O}_3^{2-}$ are isoelectronic as well as isostructural species
Statement 2 : The $d$and $d$ -orbitals do not shield the nuclear charge very effectively. Therefore, there is significant reduction in the size of the ions, just after $d$ or $f$ orbitals have been completely filled.

• A. If both Statement $1$ and Statement $2$ are true and the statement $2$ is the correct explanation of the statement $1$
• B. If both Statement $1$ and Statement $2$ are true but statement $2$ is not the correct explanation of the statement $1$
• C. If Statement $1$ is true but Statement $2$ is false
• D. If Statement $1$ is false but Statement $2$ is true

Answer 1

Answer: (D)

$S_1:S{O}_2,N{O}_3$ and $C{O}_3^{2-}$ have same number of electrons (i.e. $32$) but have different molecular geometry

$S_2$ : The $d$- and $f$ orbitals do not shield the nuclear charge very effectively. Therefore, there is significant reduction in the size of the ions, just after $d$ or $f$ orbitals have been completely filled. This is called lanthanide contraction.